This Week's Hottest Events: Free Art, Free Opera, and Oktoberfest by the Bay

On Tap: Oktoberfest by the BayTake part in the 11th annual Oktoberfest by the Bay, a festival of fine German food, the world's best beer, and authentic German music that will stick in your head through next year's celebration of our favorite European culture. As if you needed an excuse for weekend day drinking … $25-$30; Thursday, 9/23 - Sunday, 9/26; Pier 48, across from AT&T Park, oktoberfestbythebay.comOpera: Aida in the BallparkAlright, so I've been touting the opera a lot lately. But let's be real—there's no harm in adding a little culture to your life, especially when you can do it for free. AT&T Park is hosting a simulcast of the SF Opera's Aida. All you have to do is reserve a spot online and show up for the HD transmission of the opera onto a 103-foot wide scoreboard. This special performance has drawn nearly 100,000 in years past, so get on the bandwagon now. Free; Friday, 9/24; AT&T Park, 24 Willie Mays Plaza, sfopera.com/simulcast

Music: Dirty ProjectorsWhatever your feelings toward the Dirty Projectors' experimental mix of jagged harmonies, R&B-style vocals, Zeppelin-caliber guitar riffs and swelling orchestral strings, the sheer fact that the Brooklyn sextet can reproduce these sounds live onstage constitutes a feat of technical skill worth dropping $40 to see. Saturday, 9/25; The Fillmore, 1805 Geary Blvd., livenation.com. But if it's not exactly your speed, there's plenty of other great music to watch this week: Local Natives, The XX, Band of Horses, Vampire Weekend, and Big Boi.

Art: Post-Impressionism at the de Young + Cal Perfs' Free For FallIf you missed the Impressionism exhibit at the de Young, you now have one more chance to see masterpieces from the Musée d’Orsay before they return to France forever. This weekend marks the opening of the post-Impressionism portion of the show featuring famous late-19th-century paintings from the likes of Van Gogh, Gaugin, Cézanne, Toulouse-Lautrec, Seurat, and more. Think "Starry Night" up close and personal. Need we say more? $20-$25; 9/25/10 - 1/18/11; 50 Hagiwara Tea Garden Dr., deyoung.famsf.org/. And if the de Young is too high-brow for your mood, cross the bridge for Cal Performances' Free For Fall, one day of free performances by the Kronos Quartet, Mark Morris Dance Group, John Santos, Linda Tillery and the Cultural Heritage Choir, and many more. The festivities will take place at Zellerbach, Hertz, and Wheeler halls and on a stage on Lower Sproul Plaza. Gratis art always gets me going. Free; Sunday, 9/26; calperfs.berkeley.edu